Keywords

1 Introduction

China is one of the most developed countries for inland waterway transportation. 2020, the country’s inland waterways navigable mileage is 128 thousand kilometers, of which 67 thousand kilometers of graded waterways, accounting for 52.7% of the total mileage. The mileage of Class III and above waterways is 14 thousand kilometers, accounting for 11.3% of the total mileage. These waterways provide excellent support for the economic development of the areas through which they flow. They are essential to support China’s inland areas’ economic growth and significantly affect the gathering of various resource factors. For example, the GDP of the seven provinces and two cities along the Yangtze River waterway accounts for 40% of China’s total GDP. Given the prominent role of inland waterways in developing inland areas, China has made the development of inland waterway shipping a strategic priority in building an integrated transport system. Technological innovation is the key to achieving the relevant policy goals. These policies are significant to exploit the comparative advantages of inland waterways, construct an integrated transport network, and build national strength in transportation.

As the scale of inland waterway development and modernization improves, the complexity of waterway construction, operation, and management increase continuously. Integrating business logic at all levels through digitalization means simplifying workflow and enhancing work efficiency are crucial to the current development of the inland waterway shipping industry. At the same time, with the deepening of national green and coordinated development concept, inland waterways are the critical link of transportation and the important content of territorial spatial planning. There is an increasing need for information exchange between parties in the inland navigation world, which puts forward an urgent demand for the development and construction of digital waterways. Only by continuously improving the level of digitalization and informatization of waterways can we adapt to the national big data strategy and the needs of regional collaborative development.

In recent years, new concepts such as smart waterway, digital waterway, and digitalization of waterway have emerged. This paper does not explore the conceptual differences of the above terms. From the perspective of engineering application, the digital waterway in this paper refers to the comprehensive management system of digitization, networking, and visualization of inland waterway facilities and related activities by comprehensively using various information technologies such as big data, the internet of things, mapping, GIS, etc. To this end, this paper will study the basic framework system of digital waterway construction and analyze the relevant technical paths.

2 Review of Digital Waterways Development

Digital waterway is of strategic importance to the development of inland waterways, and there are many practical engineering cases in the development and construction of digital waterways in China and abroad. On the whole, foreign digital waterway construction starts earlier and plays a vital role in inland waterway transportation.

In the late 1990s, several countries started to work on information systems for inland shipping, and the EU proposed River Information Services (RIS). RIS is the harmonized information service to support traffic and transport management in inland navigation. RIS has the goal of a safe and efficient transport process and thus contributes to intensive use of inland waterways, and is open for connections to the commercial sector. The functions of the RIS cover traffic information, waterway information, traffic supervision, emergency rescue, transportation and logistics information, law enforcement information, statistical information, fee collection and other service areas. RIS is a cross-regional, cross-department and cross-business system collaboration and resource integration for inland waterway shipping. It includes interfaces with other transport modes on sea, roads, and railways. It will collect, process, assess, and disseminate fairway, traffic and transport information.

European research projects paved the way towards full deployment of RIS. For example, the Central Commission for the Navigation of the Rhine (2002) adopted the guidelines and recommendations for river information services in 2002 and a subsequent revision in 2004. Then it was adopted by the Working Party on Inland Water Transport of Inland Transport Committee of United Nations Economic Commission for Europe (2005). After the publication of the Directive 2005/44/EC (European Parliament and The Council of EU 2005), comprehensive RIS deployment projects started in all European countries with connected inland waterways. These RIS Guidelines describe the principles and general requirements for planning, implementing and operational use of RIS and related systems, laying the foundation for the widespread use of the RIS in various countries.

Since the new century, the road of digital development of Chinese inland waterways has made significant progress. Especially the Yangtze River and Xijiang River as the representative of the two major trunk channels, have long attached great importance to the role of information technology to promote the cause of shipping and achieved remarkable results in the construction of digital waterways. The large-scale information work on the Yangtze River started in 2001. So far, several channel information projects have been carried out around the information network infrastructure, channel measurement equipment, electronic channel map, and business applications. With the implementation of the projects mentioned above, the Yangtze River waterway management department has realized the data collection and real-time monitoring of navigation aid, water level, and tugboat in the waterway, as well as the digitization of the relevant business management, which has comprehensively improved the waterway maintenance management and information public service capability. With the Yangtze River electronic navigation chart and related information service system and monitoring platform, 95% of the Yangtze River waterway mileage has been digitized for maintenance management. New technologies such as BIM, unmanned aerial vehicle (UAV), unmanned ship, and Beidou navigation have been widely used in engineering scheme design, topographic survey and monitoring management, etc. The information technology has been gradually expanded to the whole waterway from some business areas or local reach.

In the standardization of digital waterways, China has introduced several industry standards, covering the project construction of digital waterways (JTS/T185-2021), quality inspection (JTS/T267-2021), information exchange (JTS/T184-2021), electronic navigation chart (JTS 195-3-2019), remote monitoring and control for navigation aids (JT/T 788-2010) and other aspects. The introduction of these standards has standardized the basic methods of digital waterway construction from different perspectives, such as data collection, information exchange, platform construction, and network deployment.

3 The Basic Framework of Digitalization System for Inland Waterway

3.1 Review of Digital Waterway Research

With the expanding demand for information and digital applications in the development of inland waterways, research in digital waterways has made great progress in the past 20 years in China.

Li (2004) presented the theoretical system and the construction frame of digital navigation channel. Then the paper discussed the realization of digital navigation channel in Ganjiang River and developed the navigation channel management and maintenance model as well as the riverbed evolvement analytic model. It integrated the one and two plane dimension mathematic model of water flow and sediment with GIS, which can greatly help us to make a decision for the implementation of channel regulation engineering. Wan et al. (2004) analyzes the origin of the Yangtze River “digital waterway”, as well as the meaning, aim and principle of building a digital waterway. The paper describes the overall frame, main contents and key technique of constructing the “digital waterway” in Yangtze River.

The above-mentioned studies put forward a preliminary concept of digital waterway construction, but they are constrained by the development stage, technical conditions, etc. In recent years, with the leap of modern science and technology, the pace of development of digitalization and informatization of inland waterway has been accelerated, and the research on digital waterway has been deepened and improved.

Li and Yan (2014) presented a new method based on the dynamic information from navigating ships to overcome the insufficient frequency based on the professional measurement in surveying and mapping, also the lack of space perception based on fixed point digital perception used Internet of things. The key technology was analyzed with multi-sensor integration, multi-source information quality evaluation, and multi-source data fusion. Then a comprehensive perception system with terminal perception, hydrographic survey, and navigating ships perception were reconstructed. This paper made an in-depth exploration of the data collection and processing involved in the construction of digital waterway. Lu (2016) proposed an overall framework of digital waterway for Yangtze River consisting of platform layer, data layer, application layer, service layer and support layer. It analyze the content of digital waterway construction plan, progress and achievements, and put forward the key requirements on the development of digital waterway for Yangtze River. Li (2017) summarized the technical research progress of inland digital waterway and briefly demonstrated the application of primary technological results in the planning, construction, maintenance, management and services of national high-class waterways, such as the Yangtze River, Xijiang River, Beijing-Hangzhou Grand Canal, etc. It pointed out the overall demands for the development of the technology from the prospective of orderly pushing forward the development of inland digital waterway. At the same, the paper discussed technical bottleneck in aspects of the perception, data, maintenance and management, public service of waterway information.

The established studies mainly combine with engineering cases related to the paper and study the ideas and ways of development and construction of digital waterways from many aspects such as main contents, technical conditions, etc. This paper attempts to build a framework for developing and constructing digital waterways in a universal sense based on the studies mentioned above, analyze its fundamental laws, and provide references for the long-term development of digital waterways in China's inland rivers.

3.2 Physical Objects of Digitization System

Digital waterway is the digital simulation and restoration of the natural world waterway development system. The construction of digital waterways is an inevitable requirement for the inland waterways themselves to improve their management level and efficiency and to realize the intelligent development of ports and shipping. The physical objects in the digital system of the waterway include not only the waterway itself but also the objects served by the waterway and the related activities, as well as the objects that have a limiting effect on water transportation activities.

Specifically, the physical objects of waterway digitization can be divided into 3 aspects, as shown in Fig. 1.

Fig. 1.
figure 1

Physical objects of the digital system.

First, the basic object, including the basic form of the river and the waterway infrastructure, is the primary carrier of the digital waterway. The basic form of the river is the spatial geographic information of the river, which involves critical indicators such as river basin, morphology, water depth, geology, water flow, and sediment movement. By carrying out the regular underwater topographic survey and studying the characteristics of water flow and sediment movement, we can provide the basic plan for building a digital waterway. The waterway infrastructure is mainly the position and maintenance scale of the channel and the navigation aids and revetment. The 2D digital channel models can be established by collecting and producing an electronic navigation chart. In turn, holographic navigation scene maps can be generated to expand the application area of the digital waterway combined with the elevation data.

Second, the service target, including ship, dock, anchorage, and water service facility. The ship data collection focuses on tracking the ship navigation trajectory and monitoring the loading and unloading activities at the quay berth. So it can realize the closed-loop tracking of the ship and cargo flow trajectory and create conditions for the logistics supply chain analysis based on port and shipping big data. The Port terminal, anchorage, and service area are the supporting facilities for ship arrival operation. Based on the electronic navigation chart, the information of wharf attributes is collected to enrich its content further, thus forming a big data resource pool for port and shipping.

Third, the conflict object, including ship lock, hydro-junction, bridge, and river-crossing pipeline, are external influencing factors for the development and construction of the waterway. Among them, bridges and pipelines have a specific constraint effect on the construction of waterway and ship navigation. Ship locks and hydro-junctions will significantly increase the complexity of ship navigation and extend the navigation time, but can improve the navigation conditions to a certain extent, thus creating the possibility for larger ships to navigate in the river. The construction of a digital waterway should comprehensively collect the information on the business attributes of the above hydraulic structures and integrate the development of the shipping industry with water conservancy and integrated transport to limit the negative impact of external factors and expand the positive effects.

In order to outline a complete digital portrait of physical object, this paper will describe each object in the following four dimensions: physical hardware, integrated management, production and operation, and time series, as shown in Table 1. These four indicators, which summarize the development and construction of various physical objects from different perspectives, can be used as the 1st level indicators of the data structure of physical objects. Combined with the characteristics of every entity, the corresponding 2nd level indicators can be further developed to form a complete indicator framework for a comprehensive description of physical objectives and as a basis for data collection and maintenance. It is important to note that each physical object contains only some of the selected metrics in Table 1, not all of them.

Table 1. Digitized content (classification of indicators)

3.3 Basic Framework

The construction of digital waterways should make full use of the existing advanced technology and adhere to the demand-oriented to meet the requirements of digital China and intelligent transportation development. The construction process should focus on resource integration, take business applications as the entry point, and promote the integration of information technology and waterway construction, maintenance, and services. At the same time, the exchange and sharing of waterway data with port, integrated transport, water conservancy, and other related departments should be strengthened to achieve cross-river, cross-business, and cross-department work collaboration and give full play to the economic and social benefits of digitalization.

This paper divides the framework of digital waterway construction into six layers: hardware foundation layer, perception layer, communication layer, data layer, support layer, and business layer, as shown in Fig. 2. The leading roles of each layer are as follows.

The hardware base layer is the basis of the digital waterway, including three physical objects and information infrastructure. Among them, the latter includes the type and quantity of hardware facilities required to construct a digital waterway, which should be determined after a comprehensive assessment based on the specific content of digitization and the scale of data. At the same time, the equipment capacity should be left with the necessary surplus to ensure that the incremental demand for data and the possible functional expansion are met shortly.

The perception layer, communication layer, and data layer are mainly to build a big data center for port and shipping. Among them, the role of the perception layer is to sense and obtain various types of information by using appropriate data acquisition means, such as arranging sensors for the physical objects of the digital waterway. The communication layer is for data from different sources, using 5G, Internet, and other technical means to transmit it back to the big data center. At the same time, the relevant operating instructions of the system will be sent down to the entity objects to realize timely remote monitoring and control. The data layer will use appropriate storage and calculation methods, such as Hadoop, according to the structural characteristics of the data, to establish a big data center for port and shipping to realize efficient storage, calculation, and interaction of all collected data.

As a unified system platform, the support layer provides essential services for users, such as identity authentication, user management, application management, etc. At the same time, the support layer also provides a critical business support platform, including the GIS platform, electronic navigation chart, etc. Various geographic elements are packaged in map services within the GIS platform to achieve comparative analysis, unified management, and display.

The business layer includes various business application modules and the working interface for users to log in and access. According to the system’s positioning, the responsibilities of the inland waterborne transport sector, and the availability of data, specific function modules can be developed and authorized for relevant users. It is worth noting that both the particular business workflow and the fusion analysis of multi-source heterogeneous data should simplify the operational logic and reduce complex human-computer interaction, thus increasing the interest and reliance of users in using the system.

Fig. 2.
figure 2

Layered architecture of digital waterway.

The above layered architecture defines the basic hardware and software environment required for the construction of digital waterway. Usually, it should optimize the content of each layer by combining the specific needs and goals of data waterway construction. On this basis, relying on digital twins technology, the management of the waterway can realize interactive mapping from physical space to digital space, which provides an efficient and convenient information platform for the administration, decision-making, and simulation analysis of the waterway.

4 The Idea of Digital Waterway Construction

4.1 Implementation Path

The construction of a digital waterway is not just simple software development but complex system engineering. It should be oriented around goals and problems and choose the optimal path suitable for engineering characteristics. Usually, the implementation of a digital waterway should focus on the following four aspects.

Firstly, set the work target of the digital waterway, and clarify the main purpose of the information system and the object of digitization. Special attention should be paid to the target audience of the digital waterway. The specific application needs of enterprise users and government users of the digital waterway are very different. The former focuses on the operational aspects of the enterprise, while the latter is primarily concerned with social attributes such as investment and services. At the same time, the waterborne transport sector should fully sort out the business needs and focus on the problems that can be solved by information technology.

Next, develop the implementation plan of the digital waterway. The focus is on developing a detailed technical scheme, sorting out business logic, and designing the user interface. It should identify the possible problems in hardware and software, data collection, technical conditions, etc., and propose reasonable solutions. To facilitate the expansion and step-by-step implementation of system functions, the necessary redundancy of software and hardware capabilities should be retained.

Thirdly, the technical standards related to the construction of digital waterways should be formulated, the specific content of the data to be collected should be clarified, and a feasible collection scheme should be formulated. Data is the most critical content of an information system. Without enough rich, accurate, and timely data, the construction goal of a digital waterway is difficult to achieve. The above work should be carried out based on the existing standards and norms and combined with the characteristics of the project and application scenario to ensure that the relevant guidelines and programs meet the needs of digital waterway development and construction.

Fourth, after the system is completed, it should be well maintained and data updated. We should develop the maintenance, security emergency, and data updating mechanism to ensure the safe and reliable operation of the system. In addition, the waterborne transport sector should budget well to provide the necessary ongoing funding for system maintenance.

4.2 Implementation Suggestions

  1. i.

    Attach great importance to data collection and continuous updating.

    Data is the core asset of a digital waterway. Great importance should be attached to the collection and continuous acquisition of waterway, port, and related data. On the one hand, it needs to improve the hardware facilities of the waterway survey and sensing network, strengthen the dynamic monitoring of the operation of the critical navigable structure, and guarantee the stability of data sources. On the other hand, to realize the normalized and digitalized supervision of inland waterway, an effective mechanism for continuous updating of data should be established, and all stakeholders should be bound to share information promptly.

  2. ii.

    Establish a unified digital waterway software system.

    The system constitutes a complete business chain of data sensing, transfer, storage, analysis, display, and service, realizing the fusion processing of multi-source heterogeneous data and providing a one-stop service. The business modules will be developed around specific work requirements to serve waterway operation and management decisions and give full play to the value of data.

    It is worth noting that, during the last two decades, a significant number of systems dealing with vessel traffic and transport management have been developed, and some are in operation. The inland waterborne transport sector is now faced with the challenge of integrating these building blocks into a common architecture.

  3. iii.

    Increase the application of new technologies.

    These new technologies are the basic guarantee for the construction of digital waterway, including but not limited to:

    • the application of Beidou navigation system in the field of waterway survey, remote monitoring and control for navigation aids, ship supervision;

    • the application of BIM and GIS in the design, construction and management of waterway engineering;

    • the application of UAV and unmanned ship in the land and underwater topographic survey;

    • the application of internet of things in the elements perception of waterway, and the big data technology in the fusion analysis of multi-source heterogeneous data, etc.

  4. iv.

    Focus on information exchange and sharing.

    The construction, management, and operation of the waterway are not the responsibility of a single department but involve the coordination of multiple departments. Therefore, the construction of the digital waterway, especially the management of data, should not be isolated. Under the premise of guaranteeing data security, the waterway data should be opened reasonably to achieve multi-sector and multi-level information exchange and sharing. Namely, it should provide diversified waterway information public services for ships, marine enterprises, management agencies, and the public.

5 Conclusions

The construction of digital waterways is to make full use of information technology to digitize all kinds of related physical objects such as waterways, wharves, and anchorage, and develop business modules to form a software system to realize dynamic simulation and effective control of the real world. It provides efficient, visualized, and accurate data analysis support and a business platform for a series of problems faced in the planning, construction, maintenance, and management of inland waterways. To effectively improve the level and efficiency of inland waterway management, this paper is dedicated to exploring the basic scheme of the digital waterway, which can help the technical selection for the planning and construction of inland digital waterway and the development of port and shipping big data center.

In general, information technology is becoming more mature and can effectively support the construction of digital waterways. Technology is no longer a constraint on the construction of the digital waterway. The key factors affecting the construction of a digital waterway are mainly the following: first, the accurate positioning of the use and target audience of the information system; second, how to effectively attract users to apply the digital waterway system to solve practical work problems. The former requires the inland waterborne transport sector to fully sort out the business needs and focus on the issues that can be solved by information technology. The latter requires that each business module design a relatively simple operation logic, reduce complex human-computer interaction, and avoid adding new burdens to users, thus increasing their interest and reliance on the use of the system.